To make tool replacement for a tool receptacle member of a tool magazine in such a way that the operator holds the tool by his hands at all times.

When the operator operates a stamping type working means 58, a piston 66 of an actuator 62 of a driving means 56 advances, and a plunger 40 is moved to the tool disengaging position against the action of an energized spring 42 furnished on a tool locking mechanism 22 of a tool receptacle member 14. Thereby the spring force applied to a sphere 36 of the tool locking mechanism 22 is disengaged, and it is possible to insert the tool 24 into a recess 26 in a tool receptacle member 14 without encountering any resistance, or to draw out the tool 24 accommodated in the recess 26 without resistance.